Berlin ; New York : Springer, [2007]

Hanioğlu, M. Şükrü

To the Editor We read the recent article by Klauser et al with great interest. While the potential implications of the findings are exciting, we have several concerns. First, the authors do not explicitly state whether electrocardiogram gating was used in their study. This is an important detail because cardiac motion artifact is a source of artifactual coloration with dual-energy computed tomography (DECT), particularly with dual-source scanners given the approximately 80-millisecond temporal difference between the 2 radiography beams. Furthermore, beam hardening artifact from calcified atheromas and partial volume effect, known sources of artifacts in the 2-material decomposition algorithm of DECT, may largely explain the findings. While patients with gout had higher prevalence of coronary calcification (55 of 59 patients [93%]) and cardiovascular monosodium urate (MSU) deposition (51 of 59 patients [86%]) than controls, the authors do not report whether the 4 patients with gout without coronary calcifications exhibited MSU deposition nor the number of controls or cadaveric hearts with coronary calcification. The images from the article show areas of green pixelization occurring adjacent to calcified plaques on grayscale computed tomography images (eg, Figure 2A and D, left anterior descending artery [yellow arrowhead]), which would favor this artifact hypothesis without additional data.

In Reply We appreciate the valuable comments of Becce et al on our article. We applied prospective electrocardiography gating using a thin-slice cardiac protocol to ensure highest spatial resolution with minimal motion artifact. A noncontrast electrocardiography-gated computed tomography (CT) examination with standardized scan parameters was performed using a 128-slice dual-source CT (SOMATOM Definition Flash; Siemens) with a detector collimation of 2 × 64 × 0.6 mm, rotation time of 0.28 seconds, and prospective electrocardiography triggering for heart rates less than 65 beats per minute (diastolic padding, 70% of RR interval) and more than 65 beats per minute (systolic padding, 40% of RR interval). Axial images were reconstructed with 0.75-mm slice width, increment of 0.5, and a medium-smooth convolution kernel (B26f). When motion artifact was present, it was distinguished by visual analysis of an experienced observer and colorized pixels related to motion were excluded.

Using within-page links presses the jumped-to content right at the very top of the viewport. This can be a problem when using a fixed header. With a bit of hackery, there are some CSS methods to insert space between the top of the viewport and the target element within a page.

Demo: Jump links and viewport positioning

Known support: varies depending on method used.

This experiment is the result of a post Chris Coyier made on Forrst. Chris’ method was to add an empty span element to the target element, shift the id attribute onto the span, and then absolutely position the span somewhere above it’s parent element.

That method works but it requires changes to the HTML. The comments on Chris’ post suggested the use of psuedo-elements or padding. This experiment expands on, and combines, some of those suggestions to show the limitations of each method and document their browser support.

Simplest method

If you need to jump to an element with simple styling then using the :before pseudo-element is a quick and simple approach.

#target:before {
   content: "";
   display: block;
   height: 50px;
   margin: -30px 0 0;
}

The drawbacks are that it requires browser support for pseudo-elements and it will fail if the target element has a background colour, a repeated background image, padding-top, or border-top as part of its rule set.

More robust method

The more robust method uses a transparent border, negative margin, and the background-clip property. If a top border is required then it can be mimicked using a pseudo-element, as described in Multiple Backgrounds and Borders with CSS 2.1.

#target {
   position: relative;
   border-top: 52px solid transparent;
   margin: -30px 0 0;
   -webkit-background-clip: padding-box;
   -moz-background-clip: padding;
   background-clip: padding-box;
}

#target:before {
   content: "";
   position: absolute;
   top: -2px;
   left: 0;
   right: 0;
   border-top: 2px solid #ccc;
}

There are still drawbacks: it requires browser support for background-clip if there is a background color, gradient, or repeating image set on the target element; it requires browser support for pseudo-elements and their positioning if a top border is desired; and it interferes with the standard use of margins.

To see these methods in action – as well as more details on the code, browser support, and drawbacks – have a look at the demo page. Please let me know if you know of better techniques.

Online Resource

€Attractive: German Cancer Research Center (DKFZ)
For more latest jobs and jobs in Germany visit brightrecruits.com

€Attractive: Johannes Gutenberg-Universität Mainz
For more latest jobs and jobs in Germany visit brightrecruits.com

€Attractive: CNRS
For more latest jobs and jobs in France visit brightrecruits.com

£Attractive: POSTECH / Max Planck POSTECH/KOREA Res. Init.
For more latest jobs and jobs in Korea, Republic Of visit brightrecruits.com

$Attractive: Pontificia Universidad Catolica de Chile
For more latest jobs and jobs in South America visit brightrecruits.com

€Attractive: IMPRS for Many Particle Systems in Structured Environments
For more latest jobs and jobs in Germany visit brightrecruits.com

€Attractive: DESY
For more latest jobs and jobs in Germany visit brightrecruits.com

Depositors to get up to Rs 5 lakh under deposit insurance on liquidation

According to the MCX data, the share of natural gas in the total volume of the exchange has almost tripled, while that of crude has reduced by more than half

Saefurahman, Ganjar, author

Interview with George A. Bray, MD, author of Effect of Dietary Protein Content on Weight Gain, Energy Expenditure, and Body Composition During Overeating: A Randomized Controlled Trial

Interview with Bradley M. Gray, PhD, author of Association Between Imposition of a Maintenance of Certification Requirement and Ambulatory Care-Sensitive Hospitalizations and Health Care Costs

Our Letters to Young Scientists columnists share insights into the postdoc application process